THE Environmental Defenders Office has called for NSW landholders to be given the right refuse coal seam gas companies access to their properties.

A federal inquiry into fracking laws began in Brisbane on Monday with the EDO backing the push for greater landholder powers.

"Under the relevant legislation (in NSW), an access agreement is to be signed before exploration for coal or unconventional gas can commence," it stated in a submission.

"However, landholders must negotiate and sign an agreement within 28 days of receiving notice from the mining company.

"If no agreement is reached, the company is entitled to force the landholder into arbitration for this purpose."

The legal group backed the private member's bill from Greens Senator Larissa Waters calling for fracking to be outlawed, saying a lack of scientific proof about its impacts existed.

"As a minimum, a national moratorium should apply to fracking until such time as the significant list of knowledge gaps highlighted in reports and peer-reviewed literature have been properly addressed," it argued.

"Until these gaps are researched and understood, it is difficult to accurately predict the longer term environmental impacts associated with the widespread use of fracking."

Fracking moratoriums already exist in several local and international jurisdictions including Victoria, Tasmania, France and Scotland.